The NEIS is suitable in a wide range of applications, where the noise of fans, motors, engines, air-conditioning, traffic etc, cause poor voice communications. The system is particularly useful for improving voice quality in medical treatment applications, especially radiotherapy, where voice communications from the bunker to the control room are greatly improved. The NEIS system consists of a robust, stylish desktop control unit with a “push to talk button”, connected to a remote “hands free” speaker unit with microphone assembly. Operation of the bhi intercom system is simple, connections being made via a single cat 5 data cable. The NEIS is pre-configured for optimum noise canceling, which is fully adaptive to changing environmental conditions.